So you expect fire discipline from a deranged lunatic on a killing spree? I wouldn’t expect them to score very high.
However I do expect good fire discipline from cops.
Do you honestly think a study on each bullet fired by criminals and by cops is possible?
Why don’t you start with the cops who went in shooting to save a suicidal man. 360+ rounds later the man was shot, a cop was shot, and another cop was dead. Only the cops had firearms and had shot each other.
But there still might be conclusions you could draw in comparison, because usually cops fire more often.